Service providers utilize Ethernet provider networks to offer services such as virtual private networks (VPNs) to their customers. To support VPNs, the Ethernet provider networks may use Virtual Local Area Networks (VLANs) to identify traffic associated with one customer's VPN from traffic associated with another customer's VPN.
VLANs provide an effective mechanism for traffic identification. However, the number of VLANs that a service provider may support on a single Ethernet provider network may be limited by the length (in bits) of a standard VLAN identifier, which is included in packets relayed by the Ethernet provider network. A longer VLAN identifier could enable service providers to support additional VLANs on a single Ethernet provider network. However, using a longer VLAN identifier would be incompatible with existing Ethernet devices. Accordingly, Ethernet provider networks may be limited in the number of VLANs that they simultaneously support.
In addition to the VLAN limitation described above, Ethernet provider networks are limited in the number of customer devices they support. For each customer device that sends packets relayed by the Ethernet provider network, the Ethernet provider network may learn one to hundreds or thousands of Ethernet Medium Access Control (MAC) addresses. Switches making up the Ethernet provider network store these learned MAC addresses. Since these switches have a limited amount of memory, the Ethernet provider network may accommodate a limited number of customer devices.
The use of VPNs facilitated by Ethernet provider networks is increasing. However, the size of Ethernet provider networks may be restricted by the VLAN limitations and customer device limitations described above.